The present invention relates to vehicle headlamps, and more particularly to a vehicle headlamp suitably applicable to a socalled "aerodynamic type headlamp" having a reduced thickness and improved aerodynamic properties.
In order to reduce the air resistance of a vehicle during travel, it is desirable to decrease the height of the vehicle body and to make the vehicle body smooth, i.e., to provide a streamlined vehicle body. Accordingly, the height of a headlamp installed on the vehicle body of this type should be made as small as possible and the headlamp installed on the sloped upper surface of the vehicle body. For this purpose, a recess is formed in front of the headlamp. The recess is covered with a lens cover having a curvature which is substantially equal to that of the vehicle body surface so that the air resistance due to the headlamp is minimized.
In the above-described headlamp, the lens cover is a transparent plate uniform in thickness, and therefore it is low in mechanical strength. This difficulty may be overcome by increasing the thickness of the lens cover. However, doing so is disadvantageous in that the increase in thickness of the cover lens results in an increase in the number of cover elements, that is, an increase in the weight of the headlamp. The mechanical strength may also be increased by providing ribs. However, the provision of the ribs makes the metal mold complicated in structure, thus increasing the manufacturing cost of the headlamp.